brcmfmac: add firmware and nvram file name for bcm4339

Add firmware/nvram file name for bcm4339 so fmac can actually be functional with
the chip.

Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Franky Lin <frankyl@broadcom.com>
Signed-off-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>